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Databases Querying Relational Databases Subqueries Subqueries

Posted by Fairooz Adams
Fairooz Adams
2,704 Points

Keep getting an error.

Hi all again, what would be the correct answer for this one?

In a car database there is a Sale table with columns, SaleID, CarID, CustomerID, LocationID, SalesRepID, SaleAmount and SaleDate and a Customer table with columns, CustomerID, FirstName, LastName, Gender and SSN. Use a subquery along with IN to list all sales to female customers. (Gender = 'F') Select all columns.

Fairooz Adams
Fairooz Adams
2,704 Points

Brendan Whiting SELECT * FROM Sale WHERE "SaleID" IN (SELECT CustomerID FROM Customer WHERE Gender = 'F');

And the error I keep getting: Bummer: Your query didn't return all columns from the Sale table for who's CustomerIDs belong to people who identify as female!

2 Answers

Steven Parker
Steven Parker
229,644 Points
Steven Parker
Steven Parker
229,644 Points

When you use "IN" with a subquery to match items, it's important to be sure the subquery is selecting the same kind of item as the one you want to match with. In your example, your subquery is selecting "CustomerID", but the WHERE clause is trying to match it with "SaleID".

Try changing your WHERE clause to match on "CustomerID" to go with what the subquery is selecting.

Fairooz Adams
Fairooz Adams
2,704 Points

Thank you! It works.

Ariadna Rodriguez
Ariadna Rodriguez
6,281 Points
Ariadna Rodriguez
Ariadna Rodriguez
6,281 Points

Here is my solution that passed;

SELECT * FROM Sale WHERE CustomerID IN ( SELECT CustomerID FROM Customer WHERE Gender = "F" );